Gilaki doesn't exist in launchpad

Thanks - I've added https://translations.launchpad.net/+languages/glk.

There are quite a lot of other steps involved in adding a new language. https://wiki.ubuntu.com/Translations/KnowledgeBase/AddingNewLanguage should help you with at least some of these.

Also, it would be helpful to know plural form information for your language so that it can be correctly translated. See https://www.gnu.org/software/gettext/manual/html_node/Plural-forms.html for technical details of what this means. Feel free to either reopen this question or ask a new one once you have that information.

Hello. I'm following those links and they're very useful.
I have some questions and I really don't know where should I ask them.
In this step my main problem is that when I want to test my glk_IR file in my local system, I get these errors:

[error] LC_ADDRESS: terminology language code `glk' not defined
[error] LC_ADDRESS: language abbreviation `glk' not defined
[error] LC_ADDRESS: language abbreviation `glk' not defined

Is seems it's because of these lines:

lang_ab "glk"
lang_term "glk"
lang_lib "glk"

But I'm sure glk is Gilaki's language code. I never seen any other codes for Gilaki.

Where should I search for this problem? Or maybe I should just ignore this?

Sorry, I'm really not enough of a C library localisation expert to be able to answer that, and I doubt anyone else reading this is either. You'll probably need to contact the glibc locale data maintainers for help.